The present invention relates to a circuit for cancelling the distortion included in a demodulated FM signal.
Although band-pass filters are included in the front end stage and intermediate frequency amplification stage of an FM receiver, the frequency vs phase characteristics of these band-pass filters do not always have an ideal linearity. Therefore, the distortion is included in an FM demodulated signal. These frequency-band characteristics vary in dependence upon changes in circumferential conditions such as the ambient temperature, moisture, and the like, and with time.
It is an object of the present invention to provide a distortion canceller to remove the distortion in a demodulated FM signal to be caused due to a non-linearity of the frequency-band characteristics at the front end stage and intermediate frequency amplification stage.
A more specific object of the present invention is to provide a distortion canceller whereby even when the frequency-band characteristics vary, it follows its change and can cancel the distortion.